Cold welding schematic

Figure 1. Schematic representation of various possible friction mechanisms (a) Geometric interlocking of asperities with typical angle 0, (b) elastic deformation (stretched dashed bonds) to interlock atoms and/or macroscopic peaks, resulting in multiple metastable states, (c) defect pinning (circles), (d) pinning by an intervening layer of weakly bound material, (e) plastic deformation or plowing, and (f) material mixing or cold welding.

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